Objective: to verify whether there are differences in the immediate effects of two different types of intervention (structured vocal warm-up and continuous singing) on aerodynamic, acoustic, and self-assessment measures in popular singers, also evaluating how individual characteristics, such as symptoms and vocal handicap, time of singing experience, age, and gender, modulate responses to interventions.

Method: Thirty singers participated in the study. All participants completed self-assessment protocols (including the Vocal Symptoms Scale – VoiSS and the Modern Singing Vocal Handicap Index – MSHI) and underwent laryngeal videostroboscopy during the initial assessment. All the singers underwent two interventions (continuous singing for 20 minutes and vocal warm-up for 20 minutes), with a minimum interval of 24 hours between them. They had their voices recorded and answered the Brazilian version of the Evaluation of the Ability to Sing Easily (EASE-Br) immediately before and after the intervention. We extracted the acoustic measurements (standard deviation of the fundamental frequency, jitter, shimmer, harmonic-to-noise ratio – HNR, amplitude difference between the first two harmonics of the voice spectrum – H1H2, glottal-to-noise excitation – GNE, and smoothed cepstral peak prominence – CPPS) and aerodynamic measurements (subglottal pressure – Psub, mean airflow rate – MFR, and glottal resistance – Psub/MFR).

Results: Baseline measures confirm group comparability for all parameters. After interventions, vocal warm-up significantly reduced EASE-Br scores and increased HNR. Continuous singing, conversely, resulted in a significant increase in MFR. A repeated-measures ANOVA confirmed a significant interaction effect for EASE-Br scores, demonstrating that vocal warm-up's superior efficacy in improving self-assessment compared to continuous singing. Aerodynamic measures showed no significant effects from interventions or interactions, except GNE, which had a significant main effect for condition, with warm-up showing a favorable increase. Individual characteristics significantly modulated responses: higher baseline score on VoiSS and MSHI predicted greater post-intervention EASE improvement, Psub increase, and shimmer reduction. Longer singing training time correlated with increased post-intervention EASE, reduced glottal resistance, and reduced jitter. Gender also interacted significantly with intervention type for jitter, with women showing greater reduction after warm-up and men after continuous singing.

Conclusion: Structured vocal warm-up significantly improves popular singers' self-assessment of vocal ease and enhances vocal quality (HNR), proving more effective in these aspects than continuous singing. While continuous singing increases mean airflow rate, it does not yield comparable self-assessment benefits. Crucially, individual characteristics, including baseline vocal symptoms, vocal handicap, prior training, and gender, significantly modulate intervention responses, underscoring the need for personalized vocal preparation strategies.